Fragile X syndrome (FXS) clinical features

1. long face
2. prominent long ear pinnae
3. high arched palate
4. mitral valve prolapse
5. dilated aortic arch
6. flat feet
7. hyperextensible finger joints in childhood
8. macroorchidism (testicular volume greater than 30 cc in adulthood)
9. soft or velvet like skin.
10. Daughters can receive premutation only, sons cannot receive gene from their father
11. Single palmar crease

rare problems-- elasticity leads to increased hernias, and dilation of ureteric root leads to hydronephrosis.

Neuropsych
1. hyperarousal to stimuli with increased sympathetic response
2. Agression, anxiety
3. Concrete thinking
4. Dramatic decline of cognition in middle or later life, due to FRMP regulating amyloid precursor protein (APP) leading to coexisting Alzheimer's disease
5. Men typically are not sexually active and do not marry (not invariable)